DESCRIPTION: The "Stroke Belt" is an area in the Southeastern US with stroke mortality rates approximately 25% above the rest of the nation, and contains a region of even higher stroke mortality (the "Stroke Buckle"). Also, African American stroke mortality is 50% higher than in whites. There are many hypotheses concerning these geographic and racial excesses in mortality, but little data to assess the causes. This proposal will address the lack of information at many levels. The role of geographic and racial differences in incidence and casefatality as contributors to differential mortality rates will be examined. Geographic and racial differences in the prevalence of a wide range of risk factors, and geographic and racial differences in the susceptibility to these factors, will be estimated. The impact of migration between regions will be evaluated. Finally, the role of candidate genes for stroke on the geographic and racial differences in stroke will be assessed. This study will recruit a nationwide cohort of 30,000 stroke-free participants over the age of 55. One-third (1/3) of the participants will be from the Stroke Belt, 1/3 from the Stroke Buckle, and 1/3 from the rest of the US. Within regions, 1/2 of the participants will be African American and 1/2 white and 1/2 male and 1/2 female. The risk factor status of participants will be established by a telephone interview, an inhome visit, and from GIS data. The cohort will be prospectively followed for 3 years for incident stroke events. This prospective cohort design offers many advantages including the direct assessment of incidence and case-fatality, and permitting the assessment of the role of risk factors that were evaluated prior to the stroke event. This study addresses the wide range of hypothesized causes of the excess stroke mortality in the Southeastern US and among African Americans, and will provide information to design interventions to reduce the excess stroke mortality in these populations.